Hi Colleen---The doc increased the pain med to every 4 hours---after a couple of days on it, he was able to cut back to every 6 hours to maintain. So far-so good on the Keytruda. No side effects! He is having a problem with nausea, but that was going on before the treatment. He is afraid to go out anywhere to eat because he is afraid of getting sick--and he loves to eat out!!!!! He does not seem to feel good today--just very quiet.